| /* Return cosine of a complex type. |

| Copyright (C) 1997-2018 Free Software Foundation, Inc. |

| This file is part of the GNU C Library. |

| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. |

| |

| The GNU C Library is free software; you can redistribute it and/or |

| modify it under the terms of the GNU Lesser General Public |

| License as published by the Free Software Foundation; either |

| version 2.1 of the License, or (at your option) any later version. |

| |

| The GNU C Library is distributed in the hope that it will be useful, |

| but WITHOUT ANY WARRANTY; without even the implied warranty of |

| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |

| Lesser General Public License for more details. |

| |

| You should have received a copy of the GNU Lesser General Public |

| License along with the GNU C Library; if not, see |

| <http://www.gnu.org/licenses/>. */ |

| |

| #include "quadmath-imp.h" |

| |

| __complex128 |

| cacosq (__complex128 x) |

| { |

| __complex128 y; |

| __complex128 res; |

| int rcls = fpclassifyq (__real__ x); |

| int icls = fpclassifyq (__imag__ x); |

| |

| if (rcls <= QUADFP_INFINITE || icls <= QUADFP_INFINITE |

| || (rcls == QUADFP_ZERO && icls == QUADFP_ZERO)) |

| { |

| y = casinq (x); |

| |

| __real__ res = (__float128) M_PI_2q - __real__ y; |

| if (__real__ res == 0) |

| __real__ res = 0; |

| __imag__ res = -__imag__ y; |

| } |

| else |

| { |

| __real__ y = -__imag__ x; |

| __imag__ y = __real__ x; |

| |

| y = __quadmath_kernel_casinhq (y, 1); |

| |

| __real__ res = __imag__ y; |

| __imag__ res = __real__ y; |

| } |

| |

| return res; |

| } |